I would go with XP over Vista just because Vista is a huge pig. A computer that can run Vista will be able to run 7 even better, so really, I'd go with 7. But if you are stuck between the two choices of XP or Vista I'd go XP.
Though if you are willing to put a SSD in the system Vista may be a tad more usable. I just found Vista used to be very bad at constantly using cpu and disk. It's an OS that likes to thrash the system a lot even when idle. Even on computers that came with it, it was bloody slow.
Sounds like you had a bad experience, and likely had bad drivers to blame.
Vista was the first NT 6.0 release. While Windows 10 has technically had the NT kernel version changed to NT 10.0, it is still basically the NT 6 kernel. Windows 8.1 was NT 6.3, 8 was 6.2, and 7 was 6.1.
Which is to say, Vista got the bad reputation of improperly coded drivers from manufacturers, while by the time later versions shipped, the driver teams had finally put out stable products.
Save for a few issues in the early days, I stayed on top of that issue and had a very stable OS, far, FAR more stable than XP, and it was certainly faster.
With each successive version of Windows, I have also noticed far fewer blue screens or other fatal errors due to any kind of driver conflict. I've experienced them, a mess of drivers can easily become a mess of drivers, but Windows holds up exceptionally well as of late.